Technical Field
The present invention relates to a piping system, and more particularly to a piping system that provides on the same assembly a flare machining mechanism that expands and flares outward pipe ends and a screw machining mechanism that causes cold-pressed transformation of the inner and outer circumferential ends of pipes, with the flare machining head and the screw machining head disposed on the same chuck to enable flare machining and screw machining by changing the machining heads or shifting their positions.
Background Art
Conventionally, pipes are joined together by a variety of methods and widely used as foundation piles for buildings as well as piping to transport fluids and air.
Of the pipes used as foundation piles for buildings, large-diameter pipes are sunk into holes dug in the ground and concrete is poured into them whereas small-diameter pipes are driven straight into the ground with a pile driver or the like.
The small-diameter foundation piles are sunk by rotating the pipes without removing earth. However, depending on the soil there is a limit to how far they can be sunk into the ground, and so they are processed by cutting or joining the ends.
Long pipes are cut into small lengths and brought to the construction site and joined together and buried in the ground as described below, although these methods of joining have until now been complicated and labor-intensive.
For example, the end of a pipe sunk into the ground is left exposed at the surface and a new pipe is connected to that portion by welding, fixed in place, and sunk further into the ground. Alternatively, a cylindrical spacer is inserted to and made to project from the top end of the foundation pile and welded thereto, after which the pipe is sunk into the ground with this portion exposed at the surface, and a further connecting pipe is inserted at the correct position using this projecting spacer as a guide, and the pipes are fixed in place by welding and then sunk into the ground. Yet alternatively, one end of the spacer is sealed, multiple projections are mounted thereon, and a spacer with multiple holes therein sealing an end that fits this end is inserted into the pipe ends and forcibly joined together using a hydraulic cylinder. Yet further alternatively, pipes are joined together by a spacer and the two pipe ends are fixed in place with a transverse pin or the like without welding.
For piping used to transport fluids or air, in a case in which the pipes are cut to a predetermined length and joined to form a predetermined piping path, the methods used to join the pipes together include: welding the outer circumferences of the joints of the pipes; welding flanges to the ends of the pipes and fastening the flanges together with nuts and bolts; joining using a sleeve-type coupling in which female screw threads are cut into the inner surface thereof; and further, flaring and machining the ends of each pipe and fixing and joining free flanges using nuts and bolts.
Pipes that become foundation piles for buildings are sunk into the ground and used for earthquake proofing, earthquake protection, and earthquake resistance. However, the depth to which the foundation piles are sunk differs depends on the condition of the ground. For this reason, when constructing buildings in densely populated residential areas, the foundation piles are cut to transportable lengths and then joined in arbitrary lengths and sunk into the ground.
In this case, the pipes are electrically welded, which means that work cannot be carried out at the construction site when it is raining.
The pipes are sometimes joined together using a specialized member such as a spacer that does not require welding bores of the pipes. However, such operations are time-consuming in that the locations where the pins or other members are to be inserted into the pipes when joining must be aligned, or a thick, expensive spacer member must be used to maintain the same strength at the pipe and the member.
Joining foundation piles by fitting a spacer with multiple projections with a spacer with multiple holes that fits this spacer and which do not require welding, in which the ends of the pipes are slightly enlarged, involves a complicated process of setting a plurality of small-scale hydraulic cylinders at the joints, and moreover the pipes to be joined must be kept perfectly vertically.
In addition, pipes are often laid in high places, requiring that welding of joints be done on scaffolding. In order to weld the entire circumference of the end of the pipe it is often necessary to assume uncomfortable positions, leading to uneven or misaligned welds and emitting sparks and sludge that pose hazards to health and surroundings.
Moreover, when pipes are changed or rearranged, it is necessary to cut the pipes and then weld them together again, which are not easy operations.
Flanged pipes can be fixed in place using nuts and bolts, and for this reason can be handled in high places comparatively easily. But it is necessary to weld the flanges to the pipes in the first place, and if this work is not done accurately fluid or gas leaks might occur once the pipes are mounted in place, or the pipes cannot be laid along a predetermined path.
It is possible to use loose flanges that are not welded to the pipes but which can be slid outward along the outer circumference of the pipe and, after the flange is fitted to the pipe, the ends of the pipe are bent outward in a flaring process. At the construction site, packing is inserted between the flared portions that are to be joined together and the flared portions are sandwiched by the loose flanges and fixed in place with nuts and bolts. This method is adopted as one capable of executing piping work with only machining and does not require welding, and can utilize the piping system of the present invention.
There is a specialized flaring machine consisting of conical machining heads of a single type that are disposed horizontal to the mouth of the pipe. The base on which the conical machining heads are disposed is spun around axles on both sides and slid along the inner circumference of the pipe until the conical machining heads are vertical to the mouth of the pipe about the axial center.
Further, there is a specialized flaring machine that is equipped with a first machining roller that flares the end of the pipe by spreading the end of the pipe to an intermediate point and a second machining roller that causes cold-pressed deformation up to a predetermined spread point.
However, although at present there are several types of flaring machines that can handle pipes from size 40 A to 500 A, these are all machines that can accommodate only a certain range of pipe sizes and are dedicated for flaring fabrication, and thus are not all-purpose machines.
In addition, there are small, specialized cold-pressed forging screw machining machines that only form the outer circumferential surface of the pipe into a projecting screw. However, to join these types of pipes together it is necessary to use a special-purpose socket and a large step is formed at the joint. For these reasons, such machines are unsuitable for machining foundation piles and are not generally used.
In addition, although there are small, specialized cold-pressed forging screw machining machines that machine the outer circumferential surfaces of pipes into male screw threads, because joining requires using a special socket above-described a large step is created at the joint, such machines are unsuitable for machining foundation piles and are not generally used.
Further, although there are cases in which the inside of the pipe is machined into concave screw threads while the outside is processed into convex screw threads, such machining shaves the ends of the pipe and thus weakens them compared to the rest of the pipe.
Moreover, because the shape of the shaved thread is an angle or even an acute angle the fitting is not easy in the event that earth and sand get into the threads. Furthermore, the shaving removes the plating and rust appears quickly, making these pipes unsuitable for use as foundation piles.
As described above, whether for building foundation piles that are sunk into the ground or for transporting fluids or air, there is a limit to how long the pipes can be at the construction site, and therefore the pipes must be cut and joined as necessary. Cutting long pipes into small sections, transporting them to the construction site, and then connecting them at the construction site is extremely laborious and time-consuming